System and method of controlling power to a non-motor load

Abstract

A motor drive for conditioning power to be delivered to a non-motor load includes a voltage feedback circuit that monitors a DC bus voltage and, based on changes in the DC bus voltage, adjusts a power conditioning scheme such that near steady-state load conditions are maintained in response to a transient load condition. The voltage feedback circuit has a voltage sensor that provides voltage feedback to a controller that determines what changes in power conditioning are needed in response to a transient load condition that manifests itself in a change in DC bus voltage.

Description

BACKGROUND OF THE INVENTION

[0001] The present invention relates generally to power conditioning and, more particularly, to a system and method of controlling power to a non-motor load using a motor drive.

[0002] Motor drives are frequently used in industrial applications to condition power and otherwise control electric driven motors such as those found with pumps, fans, compressors, cranes, paper mills, steel mills, rolling mills, elevators, machine tools, and the like. Motor drives typically provide a volts-per-hertz control and have greatly improved the efficiency and productivity of electric driven motors and applications. Increasingly, motor drives are taking the form of adjustable-speed drives (ASD) that are adept at providing variable speed and / or variable torque control to an electric driven motor. Heretofore, motor drives have been used solely to control or otherwise condition power to a motor load.

[0003] Power to non-motor loads is usually controlled through a power cond...

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